Automatic control device for the overflow valve of injectors



arch 8, 1938.

H. DEUTSCH AUTOMATIC CONTROL DEVICE FOR THE OVERFLOW VALVE OF INJECTORS Filed April 1, 1937 UNITED STATES PATENT OFFICE *AUTOMATIC CONTROL DEVICE FOR THE OVERFLOW VALVE OF INJECTORS Hans Deutsch, Vienna, Austria, assignor to the firm Alex. Friedmann, Vienna, Austria Application April 1, 1937, Serial No. 134,430 In Austria April 8, 1936 4 Claims. (Cl. 103-275) This invention relates to an injector and more flow valve, which avoids a spring for returning particularly toan automatic control device ,for the said plunger and which secures the required the usual overow valve of the injector, which movements of this plunger in any case and inhas for its object to positively close this valve dependently of the degree of friction exerted by 5 after the injector has been started, in order to the said stufling box. A further object of the avoid losses of water or steam during the operapresent invention is to provide a control device tion. Such losses may occur if the temperature of the class described, which is simple in conof the water fed by the injector surpasses 100 C. struction and reliable in operation. Further oband if at the same time the pressure prevailing jects and advantages of the invention will rein the overflow chamber exceeds the atmospheric sult from the following detailed description. 10 pressure. This may happen when for example The Figs. 1, 2, and 3 of the accompanying the Water supplied to the injector has a'relatively drawing show three different embodiments of high temperature or when a relatively large the present invention in longitudinal sections by quantity of steam is admixed to this water, as is way of example,

the case in exhaust steam injectors or in high Asshown in Fig. 1,within the housing i of the 15 pressure injectors. injector there are arranged the steam nozzle 2,

In many cases, the known control devices of the combining nozzle 3 and the delivery nozzle 4. the class referred to above comprise a plunger 5 denotes the pressure chamber'communicating having its inner end within that chamber of with the outlet of the delivery nozzle 4 and the injector wherein the feed water is set under separated from the overflow chamber 6. The pressure. This plunger passes through a stuffing water is fed from the pressure chamber 5 through box and its outer end is operatively connected the check-valve 'l into the chamber 8 adjacent to With the overflow valve so as to press this valve the water discharge opening 21 wherefrom the against its seat when the plunger is forced outwater is discharged through a feed water pipe 25 wardly by the pressure of the water. When the (not shown) into the boiler. Between the cham- 25 injector is out of operation the pressure in said bers 5k and 8 is provided an opening 9 occupied chamber is released and the said plunger is and closed by a vertically slidable piston l0. A moved back by a spring which has to overcome piston rod or plunger l2 connected to the piston the friction caused by the packing of said stufling I0 passes upwards through a stufiing box I l and box, in order to release the overflow valve and to its upper end cooperated with a lever I3 rotatably ensure that this valve can be freely lifted again mounted at 23, the opposite end of this lever coat the next starting of the ,injector and allow operating with the stem I4 of the overflow valve the steam and water to escape already at the l5 adapted to shut 01T the overflow chamber E beginning of the operation. from the overflow discharge pipe i6.

If, however, the pressure of the packing of said After the injector hasv been started the piston stuiiing box is relatively high, it may occur that IU together Vwith the plunger l2 is raised from the said spring is unable `to overcome the fricthe position indicated in the drawing by the pres tion caused by this packing so that the overflow sure arising in the chambers 5 and 8 so that the Valve is kept closed by the control device also lever I3 is swung in an anti-clockwise direction after the injector has been put out of operation. and the left-hand end of this lever strikes against 40 This results in the disadvantage that the next the stem I4 of the overflow valve l5 and presses starting of the injector is rendered diflicult yor thelatter down against its seat. By this means even impossible. In this known device, it is the overflow valve l5 is positively held in its therefore necessary that the stuing box may closed position during the operation of the innot be tightened too much and is properly lujector. Now, when the injector is put out of 45 bricated in order to maintain the friction exoperation the pressure is released in the chamerted by the packing relatively low. It occurs, ber 5, whereas inthe chamber 8 which is now moreover, that the sai-d plunger is held or bound separated from the chamber 5 by the closed in its inner position in which case undesired check valve 1 the pressure is still maintained,

overflow losses are caused. Besides this, the use this pressure prevailing in the chamber B and 50 of a spring is objectionable insofar as in the in the feed water pipe connected to the opening case of breakage of the same the operation of the 21 between the check-valve 'l and the feeding injector is heavily impaired. valve of the boiler (not shown). The difference The main object of this invention is to probetween the pressures now existing in the chamvide an automatic control device for the overbers 8 and 5 acts upon the upper side of the pis- 55 vThe difference consists in that the opening 9 and piston I0 are dispensed with, the overflow `valve I5 being directly controlled by the checkvalve I'l arranged between the lchambers 5 and 8. This valve I1 is provided with a fork I8 embracing t`he rod orplunger immediately above` a collar I9 secured thereon. When the injector is started the valve I1 lifts the plunger25 and".` the overflowv valve I5 is pressed down on its seat by the lever I3. When the injector is set out of operation the pressure prevailing in theV chamber 6 presses down the check-valve I'I and the overflow valve I5 is releasedagain.

Fig. 3 shows a particularly favourable embodiment of the present invention in which the checkvalve 2liv arranged between the chambers 5 and 6 has an annular formv and isfprovided at its upper side with a. joint surface 2| upon which mounted at 23.

` I5 down in the described manner.

may rest acollar 22 on the rod or plunger 26 which in turn'cooperates with a lever I3 rotatably The plunger 26 is provided below the collar 22 with a projection 24 having a larger diameterthan the plunger 26v and projectingdownwards into the interior of the annular valve 20 to such an extent that this projectionengages the annular valve 20, whatever the position of this valver20 and of the projection 24 may be so that the annular valvev 20 is loosely guided in a vertical direction by the projection 24 in any position.`l f j When the injector is started the feeding pressure arising in the pressure chamber 5 lifts the yannular valve 2|),as well as the projection 24 whereby the Water is vallowed. to pass from the chamber 5 into .the chamber 8 and from'the latter tothe boiler. The plunger 26 thus lifted acts upon the lever I3 which presses the overow valve After thejinjector has been setpout of operation the pressure is released inr the chamber Sand the pressure still prevailing in the chamber 8 at first forces the annular valve 20 rapidly against its seat, whereas at the first moment the plunger 26 with its projectionv 24 remains in its lifted position. Since the projection 24 occupies substantially the whole cross-section of the interior of the annular valve 20, now the pressure existing in the Ychamber 8 and acting upon the'upper side and lower side of the collar 22 results, owing to the difference between thecrosssections of the plunger 26 and of the projectionY 24, in a downwardly directed force which moves the plunger 26 downanaemiaY wards into the position indicated in the drawing, thus releasing the overflow valve I5 again.

What I claim is:-

1. In an injector an automatic control device for the overflow valve of the injector, comprising a chamber directly communicating with theoutlet of the delivery nozzlev of the injector, another chamber communicating ,with thewaterdischarge opening of the injector, a movable control mem` ber arranged between said both chambers and responsive to ther pressures prevailing in both chambers, and mechanical vmeans to transmit movement ofv said control member to the overflow valve.

2. In an injector an automatic control device for the overflow valveof the injector, comprising a chamber directly communicating with the outlet of the delivery nozzle, another chamber ad- 'pressure in the other chamber,"a check-valve arranged between said both chambers so as to allow the water to'flow from the first named chamber into 'the last named chamber and transmitting means tooperatively connect said piston with the overflow valve ofthe injector so as to press the overflow valve against its seat when said control piston is movedtowards said last named chamber. Y

3. In anrinjector an automatic control device for the overflow valve of the injector,v comprising a chamber directly communicating with the outlet ofV the delivery nozzle,-`another chamber communicating with thel water discharge opening ofthe injector, achcck-valve arranged between said both chambersand openingfinto the last named chamber, and mechanical means to said lastnamed chamber, a rod slidably projecting through an `opening in the wall of the last named chamber, `this passage `opening being tightly closedbyV the said rod, -ay collar at the inner end of said rod adapted to tightlyrest on the upperside'of said annular check-valve, a projection atthe lower side of saidA collar, said prof jection being of larger diameter than s aid rod and projecting into the interior of said annular check valve, and transmitting means to opera-lv tively connect said'rod with the overflow valve so rod is lifted.

HANS DEUTSCH.

as to press the latter against its seat when said 

